There are many polyfunctional compounds, including diols and aromatic diamines, which are known to be useful as chain extenders in the preparation of polyurethane, polyurea, and polyurethane-urea polymers and/or as curing agents for epoxy resins. None of these compounds has a reactivity such as to make it universally ideal, and many fail to provide satisfactory properties in the products made by their use. Thus, there is still a need to find other compounds capable of serving as chain extenders of curing agents.
U. S. Pat. No. 4,794,129 (Gillis et al.) teaches the use of certain imino-functional compounds as chain extenders in preparing polyureas by RIM processes, and the speculative teachings of the patent include the use as chain extenders of aromatic imines wherein the aromatic group is attached to the carbon of the imino unit.